Platform mixers or shakers are widely used in the chemical, medical, food and agricultural technology industries. Platform shakers can be used in incubators, warm rooms, environmental chambers and refrigerators for a wide range of applications including but not limited to solubility studies, extraction procedures, cell cultures, genetics research, bacterial suspensions, staining, detstaining and washing procedures. Most often, a platform shaker has a motor that is mounted on a stationary base. An eccentric drive with a counterweight supports a platform and is operatively connected to an output shaft of the motor. Therefore, as the motor output shaft is rotated, a mixing or shaking motion is imparted to the platform, thereby mixing or shaking a liquid or other material in a vessel supported on the platform.
In some laboratory applications, it is desirable to place the platform shaker in a carbon dioxide (“CO2”) incubator for mammalian cell culture. Often, when a known platform shaker is placed inside a CO2 incubator, the electrical components react with the CO2 and humidity in the incubator to form carboxylic acid. The carboxylic acid is highly corrosive to the metal components inside the platform shaker; and eventually, the electrical components short out causing the platform shaker to stop. In addition, the metallic mechanical components corrode from the elevated humidity and ph levels, and often mating parts experiencing relative motion or rotation will seize or lock up. The net result is that the platform shaker has a relatively short useful life compared to platform shakers operating in a non-CO2 rich environment. One solution to the above problem is to provide a platform shaker having a sealed housing that prevents the CO2 rich environment from reaching the interior of the shaker and contacting the electrical and mechanical components. Considering the requirement of relative motion between the platform and the stationary base, sealing the platform shaker is difficult and costly.
Therefore, there is a need for a platform shaker with an unsealed or open-to-atmosphere design that can be used in a CO2 rich environment and experience a longer useful life than known platform shakers.